Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process. Without inflammation, wounds and infections would never heal. Similarly, progressive destruction of the tissue would compromise the survival of the organism. However, chronic inflammation can also lead to a host of diseases, such as hay fever, atherosclerosis, rheumatoid arthritis, psoriasis and even cancer (e.g., gall bladder carcinoma), and acute inflammation may cause injury through overresponse to an acute stimulus. It is for that reason that inflammation is normally closely regulated by the body.
As indicated above, inflammation can be classified as either acute or chronic. Acute inflammation is the initial response of the body to harmful stimuli and is achieved by the increased movement of plasma and leukocytes (especially granulocytes) from the blood into the injured tissues. A cascade of biochemical events propagates and matures the inflammatory response, involving the local vascular system, the immune system, and various cells within the injured tissue. Prolonged inflammation, known as chronic inflammation, leads to a progressive shift in the type of cells present at the site of inflammation and is characterized by simultaneous destruction and healing of the tissue from the inflammatory process.
Acute inflammation begins within seconds to minutes following the injury of tissues. The damage may be purely physical, or it may involve the activation of an immune response. Three main processes occur: (a) increased blood flow due to dilation of blood vessels (arterioles) supplying the region; (b) increased permeability of the capillaries, allowing fluid and blood proteins to move into the interstitial spaces; and (c) migration of neutrophils (and perhaps a few macrophages) out of the venules and into interstitial spaces
One particular type of inflammatory injury is that stemming from the use of therapeutic agents, many of which are intended to produce inflammation in a diseased tissue or organ, but which unfortunately are rarely able to specifically target those regions. For example, over 80% of oral cancer patients are treated with radiation therapy and at least 75% of these individuals will develop oral mucositis. Oral mucositis also occurs in patients undergoing a hematopoietic stem cell transplant and in other cancer patients requiring radiotherapy and/or chemotherapy, and is often the most severe complication of radiotherapy. Severe oral mucositis is extremely painful and impairs oral intake. Subjects suffering from oral mucositis often require long-term pain medications to alleviate the symptoms of this condition. In addition to inflammation, both chemo- and radiation-induced DNA damage and cell death can bone marrow failure, resulting in death. These are is just two examples, if better regulated, could not only save substantially on healthcare expense, but prevent considerable suffering, loss of patient function, death.